The recipes for these tempting desserts have something in common: They're made with extra virgin olive oil. And these desserts, along with several others we're featuring, would make a great conclusion to any holiday meal.

Chefs increasingly are using EVOO in their dessert repertoires. It's not just for health reasons. It's a matter of flavor and texture.

"It seems to add an almost buttery taste," says this month's featured chef,Fran Costigan, who until recently relied mainly on canola and other "neutral" oils in her vegan desserts. "Olive oil seems to add a richness I wasn't getting with neutral oils. It's great in chocolate-baked desserts."

"I like to use the oil when I want the flavor," adds Medrich, noting that EVOO works particularly well with foods such as almonds and hazelnuts.

Chocolate Orange Almond Olive Oil Cake

We've found you can eliminate butter in many baking recipes and replace it with olive oil. Use EVOO so it equals three-quarters of the amount of butter. If a baking recipe calls for a stick of butter (8 tablespoons), for example, use 6 tablespoons of EVOO. (Click here to see a conversion table.)

Don't just stop with butter when it comes to substituting olive oil, says Medrich. "Any dessert that's already made with some kind of vegetable oil is a candidate for trying."

Carrot cake ... banana bread ... you get the picture! And if your holiday schedule means you don't have time to experiment, consider serving the desserts featured here. You and your guests won't be disappointed.

Fran Costigan suffered stomach aches as a child after eating her mother's cooking. "I grew up eating packaged foods. My mom did not like to cook," recalls Costigan, a New York pastry chef and culinary instructor. Milk, in particular, turned her stomach.

"My mother served me chocolate ice cream for breakfast, because I wasn't drinking my milk," says Costigan, who at the time didn't realize she was lactose intolerant.

Costigan's stomach woes ultimately would launch her on a career path as a pioneering vegan pastry chef preparing only vegan cakes, brownies and cookies. Dairy and all animal products - like milk, eggs, honey and some white sugars - are out for vegans. Instead, Costigan uses "wholesome, healthful and organic ingredients" like whole wheat pastry flour, organic white flour, as well as soymilk and a variety of other non-dairy milks. A mild, fruity extra virgin olive oil is often her "fat of choice."

The pages of her two acclaimed cookbooks are filled with tempting desserts like the "Chocolate Cake To Live For" or a New Orleans bread pudding with apples and pecans. Costigan has even created a gourmet vegan Twinkie that landed her an appearance on ABC's Nightline.

Costigan's timing has been impeccable. A growing number of people, including movers and shakers, are adopting a vegan regimen for health reasons. Former President Bill Clinton, who underwent bypass surgery in 2004, eats a nearly vegan diet instead of Big Macs and pork barbecue.

"The Rise of the Power Vegans," reads a headline in Bloomberg Businessweek, noting that Steve Wynn, Mort Zuckerman, and Clinton "are now using tempeh to assert their superiority."

"Vegan had been a trend. Now it's a cuisine. It's hip," says Costigan, who fields requests to prepare vegan wedding cakes for ceremonies held at venues such as New York's Metropolitan Museum of Art.

Costigan's early culinary interests began with her grandmother, who lived on the top floor of the family's Brooklyn duplex.

Six-year-old Fran would go upstairs frequently. "My grandmother loved to cook and bake. I loved being with her," Costigan recalls. The two made borscht and baked desserts, including an Eastern European fluden cake which Costigan recently "veganized" for an ethnic desserts class.

Almond and Anise Biscotti Photo by Diana: http://thechiclife.com/

Costigan launched her culinary career after she had two young children of her own. She enrolled in the New York Restaurant School and focused on desserts.

After graduation, Costigan was the pastry chef at a Manhattan gourmet takeout shop, baking muffins, scones, popovers, cookies, pies and cakes. But after several months she noticed her energy was flagging. She lacked the stamina for the job.

So Costigan quit and immersed herself in books and publications to solve her health woes. After realizing she was lactose intolerant, Costigan eliminated dairy, eggs and white sugar from her diet and felt "terrific."

The revelation spurred Costigan to become a pastry chef who prepares vegan, cakes, brownies and cookies that "taste great" - versus the "inedible brick cakes" she'd encountered up to that point.

But it wasn't easy. Vegan desserts were uncharted territory in the late 1980s. No cookbooks, role models, or formulas. "I did a lot of trial and error," Costigan says. "I was like a scientist because I knew recipes for successful vegan desserts had to be formulas, like their traditional counterparts."

She ultimately perfected a delicious chocolate cake she still prepares today. "It was like, 'Oh gosh ... I cracked the code!"